Brake operator



P 1933- H. H. SEMMES 1,928,077

BRAKE OPERATOR Original Filed.June 4, 1929 Patented 1 Sept. 26, 1933BRAKE OPERATOR Harry H. Somme-s; Chevy Chase, Md., assignor to BendixBrake Company," South Bend, 1nd,, a corporation of Illinois Originalapplication June 4, 1929, Serial'Nm $68,389: Divided and thisapplication May 10, 1930. 'Serial No. 451,362 7 i'zi oia ii s. (01.188-48) This invention relates to brake operators and more particularly,to a brake operator "of the equalizing type, and is a division of "myprior application SerialNo; 368,389, filed June 4, 1929, 5 Patent No.1,805,190. issued May 12, 1931.

i It has been proposed heretofore to equalize the thrust applied tobrake shoes by'associati'ng withthe shoes a floating operator.

These are, broadly considered, of two types. The first type comprises acam fixedly mounted on the shaft, which latter has a small degree oflateral movement, so far as .to permit equalization. In the second type,the cam is'laterally movable with respect to :the shaft. I r v Thepresent invention relates to this general type of structure but to anovel mechanism for securing equalization, I

An object'of the present invention is to provide a brake equalizingoperator of the intermesh gear type. V j a I Another object isjtoprovidea brake equalizing mechanism of the floating intermesh gear type.

A further object is to provide a novel form of equalizing brake;

With these and other equallyimportant objects in view, the inyentioncomprehends the provision of a brake actuator comprising essentially a'pair of intermesh rotating gears mounted upon a p r member which has asufiicient degree of floating movement so as to 'insure equalization ofbrake thrust.

Inorder to. render the invention more readily understood, a preferredembodiment is shown in the accompanying drawing, in which- I Figure 1 isa sectional view of a complete brak assemblage, and

Figure 2 is a cross section taken on the line 2-2 of Figure 1. As shownin the drawing, the brake assemblage may comprise a brake drum 1 withwhich is associated a braking or closure plate 2. The head of the drumis apertured as at 3 to provide for the passage of the axle member.Supported on the back plate is an anchor pin 4 which serves to mount thebrake shoes 5. Each of the shoes is provided with a friction facing 6securedtheret in any suitable manner. Positioned near any suitablesection of shoes are the return springs 7. As shown, one end of each ofthese springs is received in the apertures 9 and the other end issecured to a stub 8. As is well known, these springs serve to return theshoes to the inoperative position. In lieu of the spring shown in thedrawing, any other desired type of return mechanism may be employed.

17 in the backing plate to'the applying mecha- 'Asnoted hereinbefore,the novel actuator com-. I prises a part of rotating intermeshing gearswhich are 'floatingly mounted with respect to the shoes and to thebacking plate. In the preferred form of the invention, the actuatorincludes a plate member 10 mounted for pivotal movement upon thepin-11'. 'As shown particularly in Figure 2, this pin extends throughthe backing plate. It

'may be rigidly or detachably secured.

The floating member 10 provides the mounting mechanism for the thrustimparting elements of the actuator. 'As shown, these comprise a pair ofintermesh gears 13; mounted for rotation-upon the pivot pins 12. Thesepins, as shown, particularly .in Figure 2, extend through the floatingmember 10. To one of the gear members is at-- tached an operating arm14. As shown in the drawing, the arm is formed integrally with one ofthe gears. The end of the arm 14 is ap'ertured and Y is received withinthe furcationsofthe bifurcated member 15. This member is attached to aBow- 'den'wire or other flexible operating member 16.

This is provided'with any suitable type of covering or armor and passesout through the aperture 8 0 nism.

To each of the gear members is pivotally -attached a link 18. Pivotalmovement of this link isprovide'd by pivotally mounting it with respect.to the gears by means of the pivot pins 19, and with respect to the shoeby thepivot pins 20. Theselinks may be made up of standard constructionso as to bere'versible and interchangeable. w

The operation of the construction will have been appreciated from theforegoing description. When the pedal is depressed, the operating arm 14is displaced so as to rotate the lower sector gear in a clockwisedirection; Due to this movement, the lower link 18 will be forced downwardly and the upper link 18 forced upwardly, causing the two ends ofthe 'shoesto be spread apart to effect engagement with the drum.

Assuming that the lining of the lower shoe is more worn thanthe uppershoe, it first strikes". the drum, since the distance-between its liningand the contiguous'surface of the drum'is less than the distance betweenthe lining of the lower shoe and the adjacent surface of the drum. Atthis stage, since the lower shoe'has not engaged the drum, furtherrotation will cause the floating plate 10 to move upwardly about itspivot. Further rotation of the gears thencauses the lower shoe to engagethe drum. Continued rotation of j the gears effects an equal thrust onthe two shoes, due to the free lateral floating movement of the pivotsupon which they are mounted.

When the pedal is released, the shoes are re-' turned toinoperativeposition by the action of the return spring 7, causingcounter-rotation of the sector gears to their initial position.

While I have described a particular embodiment of my invention, it isunderstood that this is given merely for purposes of illustration;therefore, I do not wish to be-limited to the structures describedherein except as such limitations are clearly imposed by the appendedclaims.

I claim: I l

l. A brake mechanism: comprising a drum, brake shoes associatedtherewith, a brake operator including a plurality of sector gearsconnected with the shoes, a circumferentially movable. part for mountingthe gears, the operator being adapt;-

ed upon actuation to cause the shoes vto engage the drum with equalretarding force.

' 2. A brake mechanism comprising a drum, brake shoes within the drum, abrake actuator comprising intermeshed sector gears, and means tofloatingly mount the gears. I

3. A brake mechanism, comprising a drum, brake shoes associated with thedrum, an actuating mechanism for the shoes comprising a pivoted plate,sector gears pivotally mounted on the plate and pivotally connected tothe shoes.

4. A brake mechanism comprising a drum, brake shoes within the drum, anoperator comprising a pivoted plate, a pair of intermeshing sector gearspivotally mounted on the plate and links pivotally connected to eachsector gear and to an adjacent shoe. v,

5. A brake mechanism comprising a drum, a backing plate, brake shoeswithin the drum, a plate pivotally mounted on the backing plate,intermeshing sector gears rotatably mounted on the plate and pivotallyconnected to the shoes and means to rotate the gears.

,6. An equalizing operator for internal expanding brake shoes comprisinga pair of intermeshed sector gears connected to the shoes, means tooperate the gears, means to mountthe gears so as to provide a limitedcircumferential movement in unison. 1 I g V I '7. An equalizingintermeshed sector gear operator for a brake comprising a plate having apivotal mounting at one end and rotatable mounting gears at the'other.

8. A vehicle wheel brake comprising a drum, a stationary backing .platetherefor, brake shoes pivoted thereon, a plate pivoted thereto, aplurality of sector gears rotatively mounted on said plate, a pluralityof links connecting said gears to said shoes and means for actuatingsaid gears so as to cause the brake shoesto frictionally en-. gage thedrum. v

9. A vehicle wheel brake comprising a drum, a stationary backing platetherefor, a plurality of internal brake shoes, a plate substantiallytriangular in shape pivotally secured at itsapex to :the backing plate,a plurality of sector gears rotatively mounted on said plate, aplurality of links, one end of each link being pivotally connected to asector gear, the other end thereof being pivotally connected to a brakeshoe and a crank arm positioned on one of the gears and having anoperating connection adjacent the apex of the platelfor actuating saidgear so as to cause the brakershoes to frictionally engage the drum.

10. In a floating brake operator, a drum, a backing platetherefor, aplurality of brake shoes pivoted thereon, a plate pivotally mountedtheret0,,a plurality of sector gears rotatively mountedon said plate,connections between the sector gearscand the brake shoes, said plateadapted to move on said pivot in a direction suchthat each shoe willengage the drum with an equal retarding force and operating means forsaid gears provided with a joint adjacent said plate.

11. Ina floating brake operator a drum, a backing plate therefor, aplurality ofv brake shoes pivoted thereon, a plate substantiallytriangular in shape pivotally mounted at its apex to'the backing plate,a plurality of sector gearsrotatively 119 mounted onsaid platefaplurality of links, one end'of each link being connected to a sectorgear, the opposite end thereof being connected to a brake shoe, saidplate adaptedto rotate about its pivot in a direction such that eachbrake will frictionally engage the 'drum'with an equal retarding forceand operating means for said gears provided with a joint adjacent saidapex.-

12. A brake mechanism comprising a drum, brake shoes associated with thedrum, an actuat- 129 ing mechanism for the shoes comprising a 'pivotedplate, sector gears mounted rotatably' on the plate and connected to theshoes, and an op? crating arm extending fromone of said sector gears andterminating in anoperating'connection adjacent the pivot of the plate.

HARRY H. SEMMESVL

